1. Field of the Invention
The present invention relates generally to a handle operated, toggle type draw latch for joining two members and for exerting force that tends to draw the two members relatively toward each other. More particularly, the present invention relates to a handle operated toggle latch that has a lockable safety catch for securely retaining the handle in a closed position until the safety catch is operated to release the handle for movement to an open position, and that utilizes a relatively complexly configured handle that cooperates in a variety of ways with other components of the latch to provide a number of desired features such as stops to limit the ranges of movement that can be executed by relatively movable components. Other features include a selection of drawbar embodiments and a choice of pivotal connections for use in coupling a selected drawbar to the latch handle.
2. Prior Art
Toggle latches of a variety of types have been proposed for use in releasably joining two relatively movable members. Usually, what is referred to as a "toggle latch" has at least a pair of pivotally interconnected, link-like components that are "toggled" through an "over center" position to effect latching and unlatching movements.
Toggle latches that are operable to releasably join and to draw two relatively movable members toward each other are sometimes referred to as "draw latches." Usually, a toggle-type draw latch includes a latch assembly that can be mounted on-a first of two relatively movable members, and has what is referred to as a "drawbar" that can be moved, when the latch is "open," into and out of connection with a latch-engageable formation that is connected to the second of the relatively movable members. When components of the latch are moved latchingly toward a "closed" position, the drawbar serves not only to engage the latch-engageable formation to join the first and second relatively movable members but also to exert force on the latch-engageable formation that tends to move the members relatively toward each other.
While some toggle-type draw latches rely solely on tension force that is applied through over-center connected components to retain latch components in their "closed" positions, proposals have been made to use spring acting safety catches of various forms to releasably retain latch components closed. Some proposed safety catches are mere leaf springs, portions of which are deflectable for movement into and out of latching engagement with relatively movable components--an arrangement that may not be well suited for use in a high-load application where vibration is present. Another safety catch proposal calls for the use of a spring-biased slide carried on one movable component for being received in an aperture defined by another movable component--an arrangement that involves no secure connection of the safety catch to a stationary base member, and that is not lockable to secure the safety catch.
Previously proposed handle operated, toggle type draw latches have not exhibited a desired degree of versatility. Toggle latches intended for different uses have tended to utilize toggle latch components that are quite differently configured. Basic operating components of such latches have not been designed with sufficient versatility in mind to permit their use, for example, with a variety of drawbar configurations, and with a selection of drawbar-to-handle connection components that not only provide different pivotal connection characteristics but also permit a selected degree of resilience (or no resilience at all) to be incorporated into their drawbar-to-handle connections.
While proposals also have been made to provide various forms of toggle latches with component-carried apertures that are alignable to receive the shanks of padlocks when the latches are closed, the alignable apertures typically have not been associated with base-mounted safety catches.